alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE PoshC2 Downloader Activity (GET)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/tt/ll"; bsize:6; fast_pattern; http.connection; content:"Keep-Alive"; http.header_names; content:"|0d 0a|Host|0d 0a|Connection|0d 0a 0d 0a|"; bsize:22; content:!"Referer"; content:!"User-Agent"; reference:md5,71eae5c5a8c5a466c73f6a83b92dbfbc; classtype:trojan-activity; sid:2036468; rev:3; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2022_05_05, deployment Perimeter, malware_family PoshC2, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_03_14;)